Help with heat sink design [2D] Convergence Issue
 

I created a design for heat sink.

I checked the mesh quality in Gambit.

The element with the worst aspect ratio value was 2.52411

The element with the worst EquiAngle/EquiSize skew value was 0.475992.

From what I understand my meshes are fine, however I am still unable to get convergence after 1000 iterations.

Attached the model and mesh quality for reference.

What can I do for it to converge?